CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Zhijian Xiao,Wenda Yang,Jing Wang,Shuang Cao,Jingling Yang,Mingshan Zhu
Photocatalysis is a promising technology for removing low concentrations of nitric oxide (NO) from the atmosphere. However, the unsatisfactory photocatalytic NO removal efficiency and the high selectivity for NO 2 in catalysts limit the development of this technology. In this work, we used an in-situ synthesis method to incorporate Cs 3 Bi 2 Br 9 into UiO-66 for efficient and robust photocatalytic NO removal. The Cs 3 Bi 2 Br 9 /UiO-66 catalyst exhibits a 77.6 % NO removal efficiency and low NO 2 selectivity under visible light irradiation at a WHSV of 1,650,000 mL h −1 g −1 , exceeding the efficiencies of Cs 3 Bi 2 Br 9 (36.4 %) and UiO-66 (2.3 %), as well as those of most reported MOF-based photocatalysts. The synergy of weak Lewis acid sites from Cs 3 Bi 2 Br 9 in Cs 3 Bi 2 Br 9 /UiO-66 and the strong Lewis acid sites from UiO-66 promotes the enrichment of NO on the catalyst surface and act as electron traps to induce carrier separation, thereby promoting the generation of O 2 − to achieve high efficiency. This work provides a new idea for the development of catalysts in NO elimination.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
CATALYSIS LETTERS
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2022
·Vol. 153
·期 4
·1215-1226
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IF 2.936
Wang Shiqing,Li Yafei,Lan Xiaocheng,Liu Boyang,Wang Tiefeng
Ni phosphide and Lewis acid–base pair site of Al 2 O 3 were combined as highly efficient catalyst for direct amination of 1-octanol to 1-octylamine. Due to the higher dehydrogenation activity and the site isolation effect, Ni 3 P/Al 2 O 3 -TPP prepared by organophosphorus was 4.0 times more active than Ni/Al 2 O 3 and increased the selectivity to 1-octylamine from 71.4 to 92.8% at 0.4 MPa NH 3 . Graphical Abstract
研究领域:
催化化学
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材料科学
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高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
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2025
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IF 2.4
Yu Lin,Yuanzhuo Ji,Yizhe Zhang,Hualiang An,Qian Zhao,Xinqiang Zhao,Yanji Wang
BACKGROUND Maleic acid (MAc) is a high value-added oxygenic hydrocarbon derivative monomer. The synthesis of MAc from biomass-based furfural is a green process and has important academic research value. Herein, selective catalytic oxidation of renewable furfural to MAc was investigated. RESULTS The effect of using different heteropoly acids as catalyst and different organic acids/H 2 O as solvent was evaluated first, and the ‘phosphomolybdic acid + acetic acid/H 2 O’ composite system with good performance was screened out. Acetate anion acted as free radical acceptor in the reaction to stabilize furfural radical and inhibit the polymerization reaction. Under optimal reaction conditions, the conversion of furfural was 97.8%, and the MAc yield and selectivity were 58.3% and 59.6%, respectively. To further improve the selectivity of MAc, different kinds of Lewis acids were introduced to construct a Brønsted–Lewis dual-acid catalytic system. When Cu(OAc) 2 was as Lewis acid, the MAc selectivity was significantly improved to 72.5% with a furfural conversion of 72.3%. The catalytic mechanism of Brønsted–Lewis dual-acid system was finally clarified. CONCLUSION In this complex system, the synergy of Cu and Mo is responsible for the outstanding catalytic efficiency, where the Mo VI /Mo V redox can be facilitated by the redox of Cu II /Cu I with the assistance of O 2 ; acetate anion can interact with furfural radicals, thereby delaying the chain reaction of free radicals. This process makes the MAc generation reaction more dominant than the polymerization reaction, thus improving MAc selectivity. © 2025 Society of Chemical Industry (SCI).
研究领域:
化学工程
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催化化学
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高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Liangdong Hu,Lian-hua Xu,Chenjun Yang,Longfei Hong,Kai Wu,Sheng Chu,Longlong Ma,Shurong Wang,Rui Xiao,Huiyan Zhang
Lewis acid sites (LASs) are essential for the photocatalytic isomerization of biomass into high-value platform compounds. However, transient changes in the number of LASs in a photocatalytic system have not been clearly documented, often resulting in an inaccurate understanding of their role in isomerization. To address this challenge, in this study, the molecular probes glyceraldehyde was isomerized to 1,3-dihydroxyacetone (DHA, 63.5 % yield , 3 h) and fructose (47.9 % yield , 3 h) on Pt–KC 3 N 4 , with concurrent production of H 2 (233.8 μmol g −1 ). The results of in situ NH 3 –temperature-programmed desorption (TPD) characterization demonstrated that light irradiation induced the formation of transient LASs on Pt–KC 3 N 4 , and the density of acid sites observed in this study differed significantly from that observed in offline data. Furthermore, theoretical calculations demonstrated that photothermal electron redistribution on Pt–KC 3 N 4 is the main factor driving this transient LAS formation. This report describes a unique methodology to explore transient acid sites in isomerization reactions and provides insight into potential applications in the field of photocatalytic biomass valorization.
研究领域:
化学
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可再生能源
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生物质转化
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DOI
高影响因子
Energy Science & Engineering
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2019
·Vol. 7
·期 5
·2237-2246
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IF 2.893
Yuan Zhao,Hao Xu,Kaifeng Lu,Yang Qu,Lingjun Zhu,Shurong Wang
In this study, the most abundant C5 carbohydrate unit in biomass, namely xylose, was chosen as the feedstock, and its hydrothermal conversion for furfural production was carried out in a green and renewable solvent system composed of water and butanone, in order to study the role of FeCl 3 and [bmim]Cl of ionic liquid catalyst in the conversion process of xylose. A key intermediate named xylulose from Lewis acid-catalyzed xylose isomerization was quantified. It was concluded that appropriate content of FeCl 3 and [bmim]Cl favored the isomerization-dehydration reaction path along which xylose was converted into furfural, while excessive amount of either component would result in side reactions leading to furfural consumption at long reaction times. By comparison between ionic liquid catalysts that had different active metal sites, xylose conversion and furfural yields were found to increase when the Lewis acidity of the metal ions became stronger. Moreover, chlorometallate anions with better catalytic performance than the original neutral salts were formed during catalyst preparation, and in this way, the xylose conversion and furfural formation were further promoted. Finally, the optimized ionic liquid catalyst produced a highest furfural yield of 75% and xylose conversion of 99% at 140°C.
研究领域:
生物化学
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可再生能源
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Li Xia,Wenxi Zhou,Yifan Xu,Zhengqiang Xia,Xinzhi Wang,Qi Yang,Gang Xie,Sanping Chen,Shengli Gao
The introduction of rich-electron ligands is a promising strategy to improve the ligand-to-metal charge transfer (LMCT) ability of metal–organic frameworks (MOFs) for efficient photocatalytic CO 2 reduction reactions (CO 2 RR), while the resulting impaired Lewis acid sites go against stable bonding with CO 2 and hinder the electron transfering to CO 2 . It is thus the key to search a trade-off between increasing LMCT and frustrating Lewis acid. Herein, the ferrocene (Fc) modified UiO-66 series MOFs, NH 2 -UiO-66-Fc, have been prepared to optimize LMCT for boosting CO 2 RR through a simple solvent-assisted ligand incorporation (SALI) method. Theoretical calculation and systematic experiments, including photoelectrochemical measures, in situ electron paramagnetic resonance, fluorescence probe analysis and X-ray photoelectron spectroscopy indicate that with increasing Fc content, the LMCT energy of MOFs significantly decreases from 2.66 to 2.10 eV based on the established electron transfer double-channel mechanism, while the Lewis acidity of Zr sites reduces with the CO 2 adsorption energy ( E ad ) ranging from −1.061 to −0.632 eV. Through introducing an optimal Fc content, NH 2 -UiO-66-Fc (2.0) integrating satisfactory LMCT ability and Lewis acidity shows superior photocatalytic CO 2 RR performance (CO yield: 90.65 μmol·g −1 ·h −1 ), about 13 times higher than that of the unmodified MOF and superior to most reported pristine MOF photocatalysts. DFT calculation demonstrates that the excellent performance of NH 2 -UiO-66-Fc (2.0) is attributed to the lowest energy barrier of 1.50 eV for the rate-limiting step of *COOH formation. In this work, such a simple post-modification strategy for facilitating the whole electron transfer path of photocatalytic CO 2 RR will provide a new way to construct high-performance MOFs-based CO 2 RR photocatalysts.
研究领域:
材料科学
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环境科学
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化学
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DOI
高影响因子
MOLECULES
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2025
·Vol. 30
·期 7
·1457
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IF 4.6
Fenfen Guo,Yuxuan Wang,Zhicheng Jiang,Youjing Tu,Ruikai Li,Xingyu Zhang,Aoyi Tang,Yuan Liang,Lishi Yan,Hu Luo,Shenggang Li,Lingzhao Kong
The catalytic production of lactic acid from carbohydrates was considered a green way to efficiently utilize renewable biomass resources. In this study, an easy post-synthesis method was used to prepare a Sn-Beta catalyst for the production of lactic acid from glucose at 180 °C, 2 MPa, and 30 min. With optimized reaction time, temperature, pressure, and the ratio of raw material to catalyst, the yield of lactic acid reached an astonishingly high level of 76.0%. In addition, the catalyst characterizations were performed in-depth, revealing the intrinsic relationship between catalyst performance and structure, proving that the 2 wt% Sn was uniformly dispersed in the skeleton of Beta zeolite, which significantly increased the density of Lewis acid. Thus, the enhanced isomerization and retro-aldol condensation processes over the Lewis acid sites led to the high yield of lactic acid. This catalytic system kept stable after five cycles at mild conditions, showing high potential for industrial biomass utilization.
研究领域:
生物化学
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催化化学
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DOI
PubMed
高影响因子
DALTON TRANSACTIONS
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2015
·Vol. 44
·期 19
·9182-9192
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IF 4.197
Cholho Choe,Ling Yang,Zhanao Lv,Wanling Mo,Zhuqi Chen,Guangxin Li,Guochuan Yin
Redox-inactive metal ions can modulate the reactivity of redox-active metal ions in a variety of biological and chemical oxidations. Many synthetic models have been developed to help address the elusive roles of these redox-inactive metal ions. Using a non-heme manganese(II) complex as the model, the influence of redox-inactive metal ions as a Lewis acid on its catalytic efficiency in oxygen atom transfer was investigated. In the absence of redox-inactive metal ions, the manganese(II) catalyst is very sluggish, for example, in cyclooctene epoxidation, providing only 9.9% conversion with 4.1% yield of epoxide. However, addition of 2 equiv. of Al3+ to the manganese(II) catalyst sharply improves the epoxidation, providing up to 97.8% conversion with 91.4% yield of epoxide. EPR studies of the manganese(II) catalyst in the presence of an oxidant reveal a 16-line hyperfine structure centered at g = 2.0, clearly indicating the formation of a mixed valent di-μ-oxo-bridged diamond core, MnIII-(μ-O)2-MnIV. The presence of a Lewis acid like Al3+ causes the dissociation of this diamond MnIII-(μ-O)2-MnIV core to form monomeric manganese(IV) species which is responsible for improved epoxidation efficiency. This promotional effect has also been observed in other manganese complexes bearing various non-heme ligands. The findings presented here have provided a promising strategy to explore the catalytic reactivity of some di-μ-oxo-bridged complexes by adding non-redox metal ions to in situ dissociate those dimeric cores and may also provide clues to understand the mechanism of methane monooxygenase which has a similar diiron diamond core as the intermediate.
研究领域:
生物化学
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催化化学
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Weirui Chen,Muxin Lin,Jiaxin Zhou,Xukai Li,Xipeng Wei,Gaozu Liao,Jing Wang,Laisheng Li
Lewis acid site was vital center for activating O 3 during catalytic ozonation process. Herein, we proposed a strategy to enhance the Lewis acid strength of Fe-MCM-48 (FeM) by fluorination. Fluorinated Fe-MCM-48 (FFeM) exhibited the better catalytic ozonation efficiency towards Ketoprofen (KET), a kind of nonsteroidal anti-inflammatory drug. 87.4 % TOC removal was obtained by F 2.5 Fe 0.8 M/O 3 process, but only 27.5 % and 52.7 % were found by sole ozonation and Fe 0.8 M/O 3 processes, respectively. Comparative characterizations, experiments and DFT calculations showed that fluorinated FFeM was regular sphere with three dimensional duct channel and large S BET . Doping of F reduced particle size, implanted electron withdrawing Si-F group and formed the electron poor center around Fe atom, which enhanced Lewis acid strength of FFeM. Protonated hydroxyl groups on Lewis acid sites were the main active sites for O 3 activation. Greater amount of O 3 were absorbed on the surface of FFeM and the greater O 3 utilization rate, •OH and •O 2 – generation rates were obtained by FFeM/O 3 process. Common anions such as Cl − , SO 4 2− and NO 3 – and Humic acids (HA) had little effect on KET removal but inhibited TOC removal in FFeM/O 3 process. •OH, •O 2 – and Fe(IV) = O oxidation were accounted for KET degradation. 16 kinds of intermediates generated from KET degradation and 4 pathways were deduced.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Jialing Shen,Guojun Lv,Juan Deng,Shihao Su,Fuxin Wang,Shengnan Xu,Lachgar Oussama,Zhongmin Liu
UiO-66 materials have the benefit of excellent stability, porosity, huge surface area, and presence of flaws, hence designing oxidative desulfurization (ODS) catalysts based on UiO-66 is very appealing. Herein, tungsten doped UiO-66 materials were synthesized with post-doping and in situ synthesis methods, and used as heterogeneous catalysts for the room-temperature oxidative desulfurization reactions. The successful doping of tungsten into the UiO-66 framework was demonstrated by FT-IR, UV–Vis, Raman and TGA characterizations. XAS characterization disclosed that tungsten element formed Zr-O-W bond on the defect sites for the tungsten doped UiO-66 materials. At the same time, the in situ synthesized W 2 @U-150 catalyst revealed the highest 98.5% of dibenzothiophene (DBT) elimination within 1h of desulfurization reaction as well as the biggest catalytic efficiency of 17727.3 h −1 mol −1 at room temperature due to its smallest band gap energy of 3.32 eV, highest tungsten content of 9.8 %, and most Lewis acid amount of 47.1 μmol/g. In addition, the synthesized W 2 @U-150 catalyst showed excellent re-usability for five cycles.
研究领域:
材料科学
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催化化学
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环境化学
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产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
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2013
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IF 4.593
Lei Dong,Yujuan Wang,Yanzong Lv,Zhuqi Chen,Fuming Mei,Hui Xiong,Guochuan Yin
Redox-inactive metal ions have been recognized to be able to participate in redox metal-ion-mediated biological and chemical oxidative events; however, their roles are still elusive. This work presents how the redox-inactive metal ions affect the oxidative reactivity of a well-investigated manganese(II) with its corresponding manganese(IV) complexes having cross-bridged cyclam ligand. In dry acetone, the presence of these metal ions can greatly accelerate stoichiometric oxidations of triphenylphosphine and sulfides by the manganese(IV) complexes through electron transfer or catalytic sulfoxidations by the corresponding manganese(II) complexes with PhIO. Significantly, the rate enhancements are highly Lewis-acid strength dependent on added metal ions. These metal ions like Al3+ can also promote the thermodynamic driving force of the MnIV–OH moiety to facilitate its hydrogen abstraction from ethylbenzene having a BDECH value of 85 kcal/mol, while it is experimentally limited to 80 kcal/mol for MnIV–OH alone. Adding Al3+ may also improve the manganese(II)-catalyzed olefin epoxidation with PhIO. However, compared with those in electron transfer, improvements in hydrogen abstraction and electron transfer are minor. The existence of the interaction between Lewis acid and the manganese(IV) species was evidenced by the blue shift of the characteristic absorbance of the manganese(IV) species from 554 to 537 nm and by converting its EPR signal at g = 2.01 into a hyperfine 6-line signal upon adding Al3+ (I = 5/2). Cyclic voltammograms of the manganese(IV) complexes reveal that adding Lewis acid would substantially shift its potential to the positive direction, thus enhancing its oxidizing capability.
研究领域:
化学
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生物化学
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DOI
PubMed
高影响因子
FIBERS AND POLYMERS
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2025
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IF 2.3
Li Xinao,Xu Yuanyuan,Wu Jianning,Liu Zhiyong,Meng Guihua,Yang Shengchao,Guo Xuhong
Pretreatment of cellulosic materials with a Lewis acid is used to remove hemicelluloses and lower the reaction temperature of pretreatment systems. Adding Lewis acid in the pretreatment process of lignin extraction can form competitive hydrogen bonds to improve the pretreatment efficiency and the extraction rate of lignin. In this experiment, a Lewis acid (AlCl 3 ) was introduced to promote the separation of lignin by using the choline chloride/formic acid DES system. The dissolution rate of lignin was studied, as well as the effects of the molar ratio of Lewis acid/choline chloride/formic acid, reaction temperature, and reaction time on lignin structure, extraction rate, and solid residue recovery ratio. The experimental results showed that the optimal ratio of formic acid:choline chloride:AlCl 3 was 1:1:0.05. When the reaction temperature was 100 °C and the reaction time was 6 h, the solid residue recovery ratio was 33%, the extraction rate of lignin was 95.6%, and the purity was 95.0%. 2D HSQC NMR, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FT-IR) spectroscopy were used to confirm the effect of Lewis acid on the extraction efficiency and structure of lignocellulose. The extracted lignin and commercial lignin showed similar structures, and the main structural units were G units and S units. In short, the addition of a Lewis acid improved the separation of lignin.
研究领域:
生物化学
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材料科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）